PURPOSE OF THE STUDY The purpose of this study is to see if children with Duchenne muscular dystrophy (DMD) who are given glutamine (a nutritional supplement) or creatine monohydrate (a nutritional supplement) have changes in strength compared to children who are given no medicinal treatment. Children who are chosen to be in this research study will be diagnosed with DMD, be between the ages of 5 and 10 years old, and will not have participated in any other DMD clinical trials within the last year, and will not have been on medications that disqualify them from participation in this trial. All children in this clinical trial are entered at the discretion of the doctors in charge of the study. During the first and second visits, children who fulfill the criteria for participation in the clinical trial will be determined. We expect 50 subjects to participate at CINRG centers worldwide.